fix: skip UserPromptSubmit hooks for slash commands (#734)

src/hooks/index.ts

@@ -139,6 +139,7 @@ export async function runPermissionRequestHooks(
 /**
  * Run UserPromptSubmit hooks before processing a user's prompt
  * Can block the prompt from being processed
+ * Skips execution for slash commands (e.g., /help, /clear)
  */
 export async function runUserPromptSubmitHooks(
   prompt: string,
@@ -147,6 +148,11 @@ export async function runUserPromptSubmitHooks(
   conversationId?: string,
   workingDirectory: string = process.cwd(),
 ): Promise<HookExecutionResult> {
+  // Skip hooks for slash commands - they don't trigger agent execution
+  if (isCommand) {
+    return { blocked: false, errored: false, feedback: [], results: [] };
+  }
+
   const hooks = await getHooksForEvent(
     "UserPromptSubmit",
     undefined,

src/tests/hooks/executor.test.ts

@@ -184,7 +184,7 @@ describe.skipIf(isWindows)("Hooks Executor", () => {
     test("LETTA_AGENT_ID is not set when agent_id is not provided", async () => {
       const hook: HookCommand = {
         type: "command",
-        command: "echo \"agent_id:${LETTA_AGENT_ID:-empty}\"",
+        command: 'echo "agent_id:${LETTA_AGENT_ID:-empty}"',
       };
 
       const input: PreToolUseHookInput = {

src/tests/hooks/integration.test.ts

@@ -405,12 +405,12 @@ describe.skipIf(isWindows)("Hooks Integration Tests", () => {
       expect(result.blocked).toBe(true);
     });
 
-    test("receives prompt and command flag in input", async () => {
+    test("skips hooks for slash commands", async () => {
       createHooksConfig({
         UserPromptSubmit: [
           {
             matcher: "*",
-            hooks: [{ type: "command", command: "cat" }],
+            hooks: [{ type: "command", command: "echo 'should not run'" }],
           },
         ],
       });
@@ -423,9 +423,9 @@ describe.skipIf(isWindows)("Hooks Integration Tests", () => {
         tempDir,
       );
 
-      const parsed = JSON.parse(result.results[0]?.stdout || "{}");
-      expect(parsed.prompt).toBe("/clear");
-      expect(parsed.is_command).toBe(true);
+      // Hooks should not run for slash commands
+      expect(result.blocked).toBe(false);
+      expect(result.results).toHaveLength(0);
     });
   });